/**
 * @author bhouston / http://clara.io/
 *
 * Luminosity
 * http://en.wikipedia.org/wiki/Luminosity
 */

// import { Color } from "./three.module.js";
import { Color } from "three";

var LuminosityHighPassShader = {
  shaderID: "luminosityHighPass",

  uniforms: {
    tDiffuse: { value: null },
    luminosityThreshold: { value: 1.0 },
    smoothWidth: { value: 1.0 },
    defaultColor: { value: new Color(0x000000) },
    defaultOpacity: { value: 0.0 },
  },

  vertexShader: [
    "varying vec2 vUv;",

    "void main() {",

    "	vUv = uv;",

    "	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",

    "}",
  ].join("\n"),

  fragmentShader: [
    "uniform sampler2D tDiffuse;",
    "uniform vec3 defaultColor;",
    "uniform float defaultOpacity;",
    "uniform float luminosityThreshold;",
    "uniform float smoothWidth;",

    "varying vec2 vUv;",

    "void main() {",

    "	vec4 texel = texture2D( tDiffuse, vUv );",

    "	vec3 luma = vec3( 0.299, 0.587, 0.114 );",

    "	float v = dot( texel.xyz, luma );",

    "	vec4 outputColor = vec4( defaultColor.rgb, defaultOpacity );",

    "	float alpha = smoothstep( luminosityThreshold, luminosityThreshold + smoothWidth, v );",

    "	gl_FragColor = mix( outputColor, texel, alpha );",

    "}",
  ].join("\n"),
};

export { LuminosityHighPassShader };
